Why shouldn't you wear a watch?
Why shouldn't you bilateral breath? God I hate swimming so much conflicting advice out there...

I have coached and instructed a lot of folks on how to swim faster. So, yes, I can tell you a million things, but you are absolutely right, how in the bloody heck can you confirm if what I (or any coach) tells you is correct or not correct? That is a very valid point.

However, there is a super easy method to check if the stuff you are hearing is correct: videos of fast distance swimmers in competition on youtube.

So, if a coach tells you to, say, not bilaterally breath (i.e., not to breathe every 3 pulls), but instead to breathe every left pull (or every right pull), then just go on youtube and look at the fastest folks swimming in National and International swim meets. BUT not just any swimmers, but only very fast male or female swimmers who are approximately equal to you in height AND who are swimming 800-1500 meters or longer (so, if you are a triathlete, DO NOT look at sprinters and try to emulate what they do). Watch what the DISTANCE swimmers do as they race, how do they breathe?

You can also look for videos of elite or high-caliber triathlons (where there is a camera with the lead swimmers for much of the race, swim 'highlights' are kinda useless) and watch what those top swimmers do as they race in open water. The same thing applies: watch what they do as they race, how do they breathe?

Of course, you can do this check regarding nearly ANY piece of advice a coach gives you, ones about head position, arm entry, arm recovery, kick strength/frequency, body position, body roll, etc, etc, etc. You really should do this with ANY guidance that ANY coach gives you, his/her credentials or experience don't mean sh*t in this arena. The only thing that means anything is if the advice is evidence-based. (And, you're right, tons and tons of swim advice is total crock.)

Anyway, if those super fast distance swimmers (in the videos that you have spent some time carefully examining) are doing what your coach told you to do, then I would say, yes, the coach is likely on to something.

But if those distance swimmers are NOT doing what your coach told you to do, then I would say you probably need a new coach ...

In my experience, this method reduces the so-called 'conflicting' advice to close to zero. And, using this evidence-based approach, you can easily determine who the blow-hards are who make stuff up or don't understand fast swimming, and who the smart coaches are who actually deliver effective swim instruction. Finally, you can also use this method to check nearly any swim info you hear/read/see online as well.

Hope that helps,
Greg @ dsw